A graphical user interface can, in some examples, include one or more visual objects or “user interface elements,” which can include shapes, pictures, text, combinations of such elements, or the like. In various graphical user interfaces, it is possible for multiple user interface elements to be positioned on a two-dimensional display such that at least part of one or more user interface elements overlap at least one other user interface element. In other words, a first user interface element can occupy a first area on a display of the graphical user interface. A second user interface element can occupy a second area on the display of the graphical user interface, and the first area can be at least partially contiguous with the second area such that if the first user interface element and second user interface element are both presented as opaque, the one of the first and second user interface elements depicted in a higher layer of the graphical user interface at least partially occludes or covers the other of the first and second user interface elements depicted in a lower layer of the graphical user interface. The use of the term “layers” can be used interchangeably with terms such as “ordering,” “stacking,” or the like, which are typically used in drawing or presentation software, such as for example PowerPoint™ or Visio™ available from Microsoft Corp. (Redmond, Wash.), or the like. These terms refer to parameters that determine how a grouping of multiple, overlapping user interface elements is presented via a graphical user interface. User interface elements in a higher layer, those that are ordered closer to a “front” or “top” of a stack, or the like are typically shown overlaying and, if set with an opaque or at least partially opaque visual characteristic, at least partially occluding those user interface elements occupying at least some of the same area on the graphical user interface and existing in a lower layer, that are ordered closer to a “back” or “bottom” of a stack, or the like.
When multiple user interface elements overlap on a graphical user interface, a user can experience difficulty in selecting a specific one of the overlapping user interface elements. Selection of a single user interface element can be desirable for a number of reasons. For example, the user may wish to move the user interface element, change a size of the user interface element, add or alter a color or texture or pattern of a line or interior of all or part of the user interface element, delete the user interface element, move the user interface element to a different layer, or the like. Selection of a user interface element in an topmost layer of the graphical user interface can typically be relatively simple—a touch on a touch screen, a “click” or other activation of a user input device for moving a pointer or cursor on the screen (e.g. a mouse, a trackpad, a trackball, or the like), one or user inputs in conjunction with a keyboard stroke, or the like within or on the boundary of a user interface element in the top layer or within or on the boundary of a user interface element that is in a lower layer but not fully occluded by another user interface element in a higher layer is usually sufficient to select such a user interface element. However, a user interface element positioned below the upper layer and at least partially occluded by one or more user interface elements in higher layers or otherwise ordered closer to the front or top of a stack can be quite challenging to select without moving one or more of the user interface elements disposed above it in higher layers or closer to the top or front of the stack.